Re: [PATCH net-next v8 01/10] enic: verify firmware supports V2 SR-IOV at probe time

[Satish Kharat <satishkh@cisco.com>]

/"Can we get here with SR-IOV enabled? Then we want to disable it on 
failure."/

No — enic_sriov_detect_vf_type() runs during early probe, before any 
SR-IOV enablement path executes.
The auto-enable path (for pre-configured VFs at boot) runs later in 
enic_probe() and already skips V2:
if (enic->num_vfs && enic->vf_type != ENIC_VF_TYPE_V2) { err = 
pci_enable_sriov(pdev, enic->num_vfs);
The user-triggered path (sriov_configure) also checks vf_type and 
returns -EOPNOTSUPP when it is
ENIC_VF_TYPE_NONE.
So at the point where this function downgrades vf_type to 
ENIC_VF_TYPE_NONE, SR-IOV has not been enabled
  and there is nothing to disable

On 6/9/26 10:30, Breno Leitao wrote:
> On Tue, Jun 09, 2026 at 09:32:27AM -0700, Satish Kharat wrote:
>> During PF probe, query the firmware get-supported-feature interface
>> to verify that the running firmware supports V2 SR-IOV. Firmware
>> version 5.3(4.72) and later report VIC_FEATURE_SRIOV via
>> CMD_GET_SUPP_FEATURE_VER. If the firmware does not support the
>> feature, set vf_type to ENIC_VF_TYPE_NONE and log a warning so the
>> admin knows a firmware upgrade is needed.
>>
>> VIC_FEATURE_SRIOV is assigned the explicit value 4 to match the
>> firmware ABI.  Slot 3 (firmware's VIC_FEATURE_PTP) is reserved with
>> a comment rather than a placeholder enum entry, since PTP is not
>> used by the upstream driver.
>>
>> Suggested-by: Breno Leitao <leitao@debian.org>
>> Signed-off-by: Satish Kharat <satishkh@cisco.com>
>> ---
>>   drivers/net/ethernet/cisco/enic/enic_main.c   | 21 ++++++++++++++++++++-
>>   drivers/net/ethernet/cisco/enic/vnic_devcmd.h |  2 ++
>>   2 files changed, 22 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/ethernet/cisco/enic/enic_main.c b/drivers/net/ethernet/cisco/enic/enic_main.c
>> index e7125b818087..53d68272d06a 100644
>> --- a/drivers/net/ethernet/cisco/enic/enic_main.c
>> +++ b/drivers/net/ethernet/cisco/enic/enic_main.c
>> @@ -2641,8 +2641,10 @@ static void enic_iounmap(struct enic *enic)
>>   static void enic_sriov_detect_vf_type(struct enic *enic)
>>   {
>>   	struct pci_dev *pdev = enic->pdev;
>> -	int pos;
>> +	u64 supported_versions, a1 = 0;
>>   	u16 vf_dev_id;
>> +	int pos;
>> +	int err;
>>   
>>   	if (enic_is_sriov_vf(enic) || enic_is_dynamic(enic))
>>   		return;
>> @@ -2669,6 +2671,23 @@ static void enic_sriov_detect_vf_type(struct enic *enic)
>>   		enic->vf_type = ENIC_VF_TYPE_NONE;
>>   		break;
>>   	}
>> +
>> +	if (enic->vf_type != ENIC_VF_TYPE_V2)
> Can we get here with SR-IOV enabled? Then we want to disable it on
> failure.